• Transactions of Materials Processing
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• v.14 no.4 s.76
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• pp.351-359
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• 2005

The semi-solid processing is now becoming of great interest for the production of various parts by pressure die casting. Also, the rheo-casting has been substituted for thixo-casting, because the rheo-casting can control the solid particles to globular and non-dendritic solid phase. In the rheo-casting process, the important thing is to control the solid particles behavior in semi-solid materials. So in this paper, to control solid particles behavior in semi-solid materials, we experimented about the die filling tests during the semi-solid die casting in 0.3, 0.4, 0.5 and 0, 6 solid fraction. The die filling in semi-solid die casting were simulated by MAGMA soft/thixo module. By the die filling tests and computer simulation, the effect of solid particles behavior in rheology flow had been investigated.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2004.10a
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• pp.664-667
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• 2004

The semi-solid processing is now becoming of great interest for the production of various parts by pressure die casting. Also, the rheolory casting has been substituted for thixo casting, because the rheology casting can control the solid particles to globular and non-dendritic solid phase. In the rheology casting process, the important thing is to control the solid particles behavior in semi-solid materials. So in this paper, to control solid particles behavior in semi-solid materials, we experimented about the die filling during the semi-solid die casting in 0.3, 0.4, 0.5, 0,6 solid fraction. The die filling in semi-solid die casting were simulated by MAGMAsoft/thixo module. By the die filling tests and computer simulation, the effect of solid particles behavior in rheology flow had been investigated.

• Transactions of the Korean hydrogen and new energy society
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• v.27 no.2
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• pp.211-219
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• 2016

To develop an ash separator for the solid fuel chemical looping combustion system, effects of operating variables such as solid injection nozzle velocity, diameter of solid injection nozzle, gap between solid injection line and vent line, vent line inside diameter, and solid intake height on solid separation rate and solid separation efficiency were measured and discussed using heavy and coarse particle and light and fine particles mixture as bed material in an acrylic fluidized bed apparatus. The solid separation rate increased as the solid injection nozzle velocity and the diameter of solid injection nozzle increased. However, the solid separation rate decreased as the gap between solid injection line and vent line, the vent line inside diameter, and the solid intake height increased. The solid separation efficiency was in inverse proportion to the solid separation rate. In this study, we could get high solid separation rate up to 2.39 kg/hr with 91.6% of solid separation efficiency.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2003.06a
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• pp.1601-1604
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• 2003

This paper describes a split operation for generation of core and cavity plates of an injection mold for a pseudo-solid model of a plastic part. Here, a pseudo-solid model means a sheet model that looks like a solid model. but whose boundary is not closed. When a solid model created in a different CAD system is imported through standard data exchange format, a pseudo-solid model is created in most cases as tolerance or some other problems make sewing operation failed. As most existing mold design system based on solid modeling kernels require a complete part solid model, mold designers have to do time-consuming healing operations to convert a pseudo-solid to solid. The essential capability of mold design system is the split operation for generation of core and cavity plates. Thus. we developed a split operation for pseudo-solid part model to eliminate or reduce healing preprocessing for mold design.

• Korean Journal of Computational Design and Engineering
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• v.10 no.3
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• pp.151-161
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• 2005

This paper describes the parting and Boolean operations for a pseudo-solid model of a plastic part, and their application to injection mold design. Here, a pseudo-solid model means a sheet model that looks like a solid model, but its boundary is not closed. When a solid model created in a different CAD system is imported through a standard data exchange file format, in most cases, a pseudo-solid model may be created due to tolerance or some other problems. However, most existing mold design systems based on solid modeling kernels require a complete part solid model. Therefore, mold designers have to do time-consuming healing operations to convert a pseudo-solid to solid. To eliminate or reduce the healing pre-process for mold design, in this paper, we proposed the parting and Boolean Operations on pseudo-solid part models. This paper also describes their detailed implementation and a case study.

• Korean Chemical Engineering Research
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• v.47 no.3
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• pp.337-343
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• 2009

To apply to novel two-interconnected fluidized beds system for selective solid circulation, a solid separator and a solid circulation system were developed. The solid separation rate increased as the gas velocity through the solid injection nozzle, solid height, and diameter of solid injection nozzle increased. However, the effect of the fluidization velocity was negligible. Coarse($212{\sim}300{\mu}m$) and fine($63{\sim}106{\mu}m$) particles were separated using the solid separator and the solid separation rate was ranged from 66 to 453 g/min. The solid circulation rate increased as the gas velocity through the solid injection nozzle, solid height, and the number of solid intake holes increased. However, the effect of the fluidization velocity was negligible. Fine particle was circulated using the solid circulation system and the solid circulation rate was ranged from 65 to 390 g/min. We also proposed two interconnenced fluidized beds system for selective solid circulation equipped with the developed solid separator and the solid circulation system. Long-term operation of continuous solid circulation up to 20 hours has been performed to check feasibility of stable operation. The pressure drop profiles in two beds and the solid separation rate were maintained steadily, and therefore, we could conclude that solid circulation was smooth and stable.

• Ceramist
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• v.22 no.2
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• pp.170-181
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• 2019

All-solid-state batteries have received increasing attention because of their high safety aspect and high energy and power densities. However, the inferior solid-solid interfaces between solid electrolyte and active materials in electrode, which cause high interfacial resistance, reduce ion and electron transfer rate and limit battery performance. Recently, spark plasma sintering is emerging as a promising technique for fabricating solid electrolytes and composite-electrodes. Herein, this paper focuses on the overview of spark plasma sintering to fabricate solid electrolytes and composite-electrodes for all-solid-state batteries. In the end, future opportunities and challenges associated with SPS technique for all-solid-state batteries are described.

• Journal of Microbiology and Biotechnology
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• v.26 no.1
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• pp.110-119
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• 2016

High-solid anaerobic digestion of sewage sludge achieves highly efficient volatile solid reduction, and production of volatile fatty acid (VFA) and methane compared with conventional low-solid anaerobic digestion. In this study, the potential mechanisms of the better performance in high-solid anaerobic digestion of sewage sludge were investigated by using 454 high-throughput pyrosequencing and real-time PCR to analyze the microbial characteristics in sewage sludge fermentation reactors. The results obtained by 454 highthroughput pyrosequencing revealed that the phyla Chloroflexi, Bacteroidetes, and Firmicutes were the dominant functional microorganisms in high-solid and low-solid anaerobic systems. Meanwhile, the real-time PCR assays showed that high-solid anaerobic digestion significantly increased the number of total bacteria, which enhanced the hydrolysis and acidification of sewage sludge. Further study indicated that the number of total archaea (dominated by Methanosarcina) in a high-solid anaerobic fermentation reactor was also higher than that in a low-solid reactor, resulting in higher VFA consumption and methane production. Hence, the increased key bacteria and methanogenic archaea involved in sewage sludge hydrolysis, acidification, and methanogenesis resulted in the better performance of high-solid anaerobic sewage sludge fermentation.

• Korean Journal of Computational Design and Engineering
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• v.9 no.2
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• pp.122-132
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• 2004

Progressive mesh representation and generation have become one of the most important issues in network-based computer graphics. However, current researches are mostly focused on triangular mesh models. On the other hand, solid models are widely used in industry and are applied to advanced applications such as product design and virtual assembly. Moreover, as the demand to share and transmit these solid models over the network is emerging, the generation and the transmission of progressive solid models depending on specific engineering needs and purpose are essential. In this paper, we present a Cellular Topology-based approach to generating and transmitting progressive solid models from a feature-based solid model for internet-based design and collaboration. The proposed approach introduces a new scheme for storing and transmitting solid models over the network. The Cellular Topology (CT) approach makes it possible to effectively generate progressive solid models and to efficiently transmit the models over the network with compact model size. Thus, an arbitrary solid model SM designed by a set of design features is stored as a much coarser solid model SM/sup 0/ together with a sequence of n detail records that indicate how to incrementally refine SM/sup 0/ exactly back into the original solid model SM = SM/sup 0/.

• Journal of the Korean Society of Industry Convergence
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• v.4 no.1
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• pp.3-9
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• 2001

Many products related to automobile and airplane have been manufactured by semi-solid process. There are many parameters in semi-solid process such as punch velocity, die temperature, and solid fraction of material. Among these parameters, solid fraction of material is one of the most important factors to determine quality of product. To obtain solid fraction of a certain semi-solid product is very necessary and useful for inspecting and analyzing the product. In this paper, image analysis program for microstructure by semi-solid forming process has been developed with the simple apparatus such as a personal computer and scanner, instead of expensive image analyzer.